红菜薹小孢子培养技术研究

以5个红菜薹品种为试材,从花蕾的选择、影响小孢子出胚的关键因素、胚状体成苗及生根条件等方面对红菜薹小孢子培养技术进行了系统研究。结果表明:小孢子培养取样最佳时期为单核靠边期,瓣萼比在0.626~0.834之间;基因型不同对小孢子培养影响很大,以H13-3出胚率最高,为2.78个/皿;胚状体诱导的最适培养基为Keller-13添加6-BA 1.0 mg/L+KT1.0 mg/L+NAA0.5 mg/L,出胚率为2.67个/皿,且70%以上为子叶形胚;转接胚状体最适宜的胚龄为15~25 d,成苗率在65%~83%;再生植株生根培养基添加NAA最适浓度为0.4 mg/L,侧根多而粗壮,移栽成活率高。     

秋水仙碱对油菜小孢子产胚率和再生植株二倍体率的影响

为探索适用于长江流域主产区生态条件下的甘蓝型油菜小孢子培养技术中最佳秋水仙碱浓度,以2个适合进行小孢子培养的油菜材料为对象,研究了4种不同浓度(0、100、200和400mg/L)的秋水仙碱处理对小孢子产胚率和二倍体率的影响。结果表明,200mg/L的秋水仙碱处理24h后,小孢子的产胚率和二倍体率都达到最大,与对照有显著的差异。用这一浓度,对40份不同基因型油菜的小孢子进行诱导培养,结果表明不同基因型油菜小孢子产胚率和二倍体率存在较大差异,小孢子产胚率为0.12~10.39胚/蕾,再生植株二倍体率为26.7%~90.0%。按照种皮颜色分类后发现,黄籽油菜与黑籽油菜的小孢子产胚率有显著差异,而二倍体率因材料基因型而异,推测油菜种皮颜色与小孢子的产胚率有一定相关性,而与再生植株二倍体率的相关性不大。     

白菜游离小孢子培养高频胚诱导技术体系优化

为优化白菜游离小孢子培养高频胚诱导技术体系,以20个不同基因型白菜栽培品种为供试材料,对影响白菜游离小孢子胚诱导和植株再生因素进行研究。结果表明:有14个基因型产生了小孢子胚,不同基因型之间胚诱导率差异显著,表明基因型是影响小孢子胚发生的主要因素;通过对白菜游离小孢子培养高频胚诱导技术体系的优化,胚诱导率明显提高,最优组合为盛花期取蕾;花瓣长与花药长比为0.5~0.75;4℃低温预处理1 d;150 g/L蔗糖的NLN培养基33℃高温热激2 d,重新离心更换130 g/L蔗糖的NLN培养;激素最优组合为6-BA0.1 mg/L、NAA 0.5 mg/L;在培养基中添加活性炭有利于胚的形成,最佳浓度为0.5 g/L。     

采用甘蓝型油菜离体小孢子染色体加倍来提高双单倍体植株的生产效率

该文比较了甘蓝型油菜小孢子产生植株染色体加倍的三种方法；秋水仙碱处理小孢子再生植株，秋水仙碱处理小孢子诱导的胚和秋水仙碱处理离体小孢子。处理整株，有５３％的处理植株结实，但植株生长迟缓，结实率下降。用秋水仙碱处理小孢子诱导胚，植株加倍率为３２％。秋水仙碱直接处理离体小孢子可使７０％的植株整体加倍，同时还刺激了培养小孢子的胚胎发生，从而提高植株再生率。     

枇杷花药胚状体诱导条件的优化

以‘大五星’枇杷花药为外植体,研究小孢子发育时期、低温处理及植物生长调节剂对花药愈伤组织诱导及胚状体发生的影响。结果表明：枇杷小孢子发育时期与花蕾横径存在对应关系,横径为4.68～5.28 mm的枇杷花蕾处于单核靠边期,此时期的小孢子胚状体诱导率最高,为25.05％;经4 ℃低温处理2 d的花药愈伤组织诱导率最高,达69.93％;花药愈伤组织诱导的最适培养基是MS+2,4-D 0.5 mg/L+6-BA 2.0 mg/L,愈伤组织诱导率为78.22％;枇杷花药愈伤组织诱导胚状体的最适培养基为MS+ZT 0.05 mg/L+NAA 0.01 mg/L+IBA 0.05 mg/L,胚状体诱导率为25.56％。     

甘蓝型杂交油菜亲本的小孢子培养技术研究

通过对42份甘蓝型油菜(Brassica napus)不同基因型材料的小孢子培养研究,结果表明不同基因型材料的小孢子产胚率存在明显差异,但pol-CMS的恢复系与保持系之间的胚状体产量差异不显著,恢复或保持基因不影响小孢子成胚率,说明通过小孢子培养快速纯合pol-CMS杂交亲本是可行的.胚状体直接成苗率与培养基中琼脂浓度、培养温度及供体材料基因型有关,胚状体经低温诱导及适当增大培养基中琼脂浓度可有效提高胚状体直接成苗率.4℃低温处理10d和培养基琼脂浓度高于1.2%均可提高胚状体的直接成苗率,并以1.5%琼脂浓度效果较好.     

小孢子培养技术纯化 与选育Pol TCMS不育两用系

利用甘蓝型油菜游离小孢子培养技术,获得了4个甘蓝型Pol细胞质温敏雄性不育两用系( Pol TCMS)的 DH系,说明通过小孢子培养技术纯化选育Pol TCMS不育两用系是可行的。研究结果表明: Pol TCMS不育两用系 的最佳取样时期为第一朵花开放前的4～7d;在NLN培养基中补充0. 05mg/L的细胞分裂素6 - BA可以显著提高 出胚频率;游离小孢子首先在35℃高温条件下热激48h,然后转入到22℃恒温箱中连续暗培养效果最佳,其出胚频 率显著高于其他3种温度组合;胚状体在8～10℃条件下低温诱导两星期,能够显著提高其再生频率。     

γ射线和X射线对甘蓝型油菜小孢子胚状体再生的影响

采用60Co-γ射线辐照甘蓝型油菜初花期植株和X射线辐射甘蓝型油菜小孢子发育到单核晚期至二核早期的花蕾后,分离小孢子进行培养诱导胚状体和植株,探讨了适宜油菜小孢子诱变的剂量和诱变方法.结果表明,γ射线对油菜离体小孢子胚状体的发生和发育均有很大的抑制作用,15Gy和40Gy处理平均每花蕾小孢子的产胚量分别是0.574和0.268个,40Gy可作为小孢子诱变的参照剂量.X射线对4个基因型离体小孢子胚状体再生也有影响,40Gy处理平均每蕾小孢子产胚4.086个,80Gy处理为0.834个,120～200Gy处理下降到0.021～0.019个,120Gy以上的处理剂量严重阻碍了小孢子胚的发生.采用X射线80～120Gy较适宜油菜小孢子诱变.     

不同基因型菜心游离小孢子培养和植株再生

以11个不同基因型的菜心栽培品种为试材,研究不同培养条件对菜心游离小孢子胚诱导和植株再生的影响。结果有7个基因型材料获得小孢子胚,从不同基因型诱导形成胚的频率存在显著差异,表明基因型是影响菜心小孢子胚发生的主要因素;第1天热激培养时用170 g/L高浓度蔗糖培养之后转换成含130 g/L蔗糖培养基能显著提高小孢子胚诱导率;0.05 mg/L 6-BA+0.2 mg/L NAA能促进菜心小孢子诱导成胚;添加0.4 mg/L GA3可显著提高菜心小孢子胚芽诱导率和平均每胚出芽数。7个基因型材料均诱导出再生植株,植株诱导率为100%。     

可可体细胞胚胎发生及植株再生体系的构建

以可可（TheobromaCac0L.）的子叶为外植体,通过体胚发生途径,诱导再生可可植株。各培养阶段的优化培养基和培养条件为∶（1）愈伤组织诱导培养基（PCG）∶改良DKW+2,4-D3.0mgL+KT1.0mg几+TDZ 0.01mgL,在28+2）℃（以下培养温度均同）温度条件下,暗培养20d,诱导率为96.67%;（2）愈伤组织增殖培养基（SCG）∶改良DKW＋2,4-D 3.0mgA+KT1.0mg九,暗培养20d;（3）胚状体诱导培养基（ED）∶改良DKW+Sucrose30gL,暗培养60~150d,胚状体诱导产生并发育成熟,胚状体的诱导率为333%;（4）成熟胚诱导成苗∶①PEC培养基为∶改良DKW+Ghrose20gl+Sucrose10gL,光照为16h/d,培养60d;②采用RD培养基∶改良DKW+BA1.5mgl+AA0.5mgl,光照为16h/,培养3090d后,可得到完整的植株,再生植株的诱导率为 42%。     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

Novel food and non-food uses for sorghum and millets

Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.     

In vitro antimicrobial activity of different accessions ofSolanum commersonii Dun. from Uruguay

Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.     

Extreme resistance to infection by potato virus X in genotypes of wild tuber-bearingSolanum species

Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X¹ (also called RX_act).     

Cyanobacteria Secondary Metabolites as Biotechnological Ingredients in Natural Anti-Aging Cosmetics: Potential to Overcome Hyperpigmentation,Loss of Skin Density and UV Radiation-Deleterious Effects

The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O₂^•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O₂^•− scavenging, (IC₅₀ = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC₂₅ = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC₅₀ = 863 µg/mL; elastase, IC₅₀ = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O₂^•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.     

Marine Pharmacology in 2009–2011: Marine Compounds with Antibacterial,Antidiabetic, Antifungal,Anti-Inflammatory,Antiprotozoal, Antituberculosis,and Antiviral Activities; Affecting the Immune and Nervous Systems,and other Miscellaneous Mechanisms of Action ?

The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.     

Recent Modifications of Chitosan for Adsorption Applications: A Critical and Systematic Review

Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules contributes to many possible adsorption interactions between chitosan and pollutants (dyes, metals, ions, phenols, pharmaceuticals/drugs, pesticides, herbicides, etc.). These functional groups can help in establishing positions for modification. Based on the learning from previously published works in literature, researchers have achieved a modification of chitosan with a number of different functional groups. This work summarizes the published works of the last three years (2012–2014) regarding the modification reactions of chitosans (grafting, cross-linking, etc.) and their application to adsorption of different environmental pollutants (in liquid-phase).